TOMOYO: Use mutex_lock_interruptible.
Some of TOMOYO's functions may sleep after mutex_lock(). If OOM-killer selected
a process which is waiting at mutex_lock(), the to-be-killed process can't be
killed. Thus, replace mutex_lock() with mutex_lock_interruptible() so that the
to-be-killed process can immediately return from TOMOYO's functions.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 3c86bbc..8f34036 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -874,13 +874,13 @@
static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
int profile)
{
- static DEFINE_MUTEX(lock);
struct tomoyo_profile *ptr = NULL;
int i;
if (profile >= TOMOYO_MAX_PROFILES)
return NULL;
- mutex_lock(&lock);
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ return NULL;
ptr = tomoyo_profile_ptr[profile];
if (ptr)
goto ok;
@@ -895,7 +895,7 @@
mb(); /* Avoid out-of-order execution. */
tomoyo_profile_ptr[profile] = ptr;
ok:
- mutex_unlock(&lock);
+ mutex_unlock(&tomoyo_policy_lock);
return ptr;
}
@@ -1090,7 +1090,8 @@
return -ENOMEM;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
- mutex_lock(&tomoyo_policy_lock);
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ goto out;
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (ptr->manager != saved_manager)
continue;
@@ -1107,6 +1108,7 @@
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
+ out:
tomoyo_put_name(saved_manager);
kfree(entry);
return error;
@@ -1287,7 +1289,8 @@
name.name = domainname;
tomoyo_fill_path_info(&name);
- mutex_lock(&tomoyo_policy_lock);
+ if (mutex_lock_interruptible(&tomoyo_policy_lock))
+ return 0;
/* Is there an active domain? */
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
/* Never delete tomoyo_kernel_domain */